Tertiary-amino-alkylated primary amines



United States Patent ()fifice SZQIAZZ Patented Aug. 17, 1965 3,201,472'IERTiARY-AMlNO-ALKYLATED PARY ES John D. Spivack, Spring Valley, N.Y.,assignor to Geigy Chemical Corporation, Ardsley, N.Y., a corporation ofDelaware No Drawing. Original application Dec. 2, 1958, Ser. No.777,587. Divided and this application Mar. 28, 1962, Ser. No. 188,598

3 Claims. (Cl. 260583) The present application is a division ofcopending application, Serial No. 777,587, filed December 2, 1958, nowUS. Patent No. 3,151,160.

The present invention relates to a novel process for the preparations ofalkylene polyamines as well as of polya-lkylene polyamines. Thesepolyaminessome of which are known and others of which are newarecharacterized in that the molecule thereof comprises at least onetertiary amino group joined via an alkylene radical to at least oneprimary amino group. Representative of these alkylene polyamines andpolyalkylene polyamines are those which may conveniently be representedby the following formula:

CH2 CIJHNHQ :7 Rs wherein R is a higher alkyl group, i.e. one containing6 to 18 carbon atoms, and preferably 8 to 12 carbon atoms, and R has theprecedingly-recited significauces.

Prior to the present invention, the two most commonly and generallyemployed methods for preparing polyamines having at least one tertiaryamino group and a primary amino group separated from each other by analkylene radical were:

(i) A-lkylation of a secondary amine;

(ii) Gabriels synthesis using potassium phthalirnide.

The alkylation reaction is outlined in the following equation:

NH NHgCH OHzX b where X is a halogen atom or an OSO H group.

In order to minimize the extent to which undesired further alkylationoccurs On the product, a very large excess of reactant amine V isemployed. Thus the method involves recovery losses of reactant amine.Furthermore, this method is limited to the production of only thesimpler diamines, because the inherent non-selective nature of thereaction leading to more or less random substitution of otherreplaceable hydrogens results in a drastic reduction in yields in thecase of somewhat more complex reactant amines.

' The Gabriel synthesis of amines may be represented as follows:

This method is not only relatively ineflicient because it involves amuch larger number of steps, but also because byproduct reactions ineach one of the steps serves to decrease very markedly the overall yieldof the final amine.

' new and practically, as well as economically, superior process for thepreparation of the aforementioned type of polyamines represented adesideratum in the art. A primary object of the present invention is thesatisfaction of this desideratum. A further object is, incidentally, toprovide valuable new compounds, the hereinbefore-mentioned substituteddialkylenetriamines. These objects are realized by the presentinvention, according to which, briefly stated, an appropriate tertiaryaminoalkyl primary amide-advantageously obtained by causing ammonia or aprimary or secondary amine to be added across the olefinic double bondof an a,/3-unsaturated primary amideis converted into the correspondingamine having one less, carbon atom by treatment of the amide with analkaline solution of halogen, eg, of chlorine or of bromine. Theefiective treating agent for such conversion may conveniently take theform of an aqueous solution of an alkali metal hypohalite.

The conversion according to the instant invention may be illustrated, inone of its simplest forms, by the follow mg:

wherein R R and R have the precedingly-recited significances, each of Rand R is a member selected from the group consisting of alkyl, phenyl,carbamoylalkyl and polycarbamoylalkylaminoalkyl (all these alkyls beinglower alkyls), M represents an alkali metal ion, and X representschlorine or bromine.

The preparation of the starting amide may be illustrated wherein R R andR have the precedingly-recited significances.

Similar equations may be written in the case of the alkylene polyamines,or where the amide preparation involves the use of ammonia, suchequations being more complicated in form but not in concept. For examplethe reactions employing ammonia and acrylamide may be represented asfollows:

NCHrCH2NHz SNaCl N82C03 H 0 CHICHZNHI The reactions employingethylenediamine and acrylamide may be illustrated as follows:NH:CHzCHgNH2+4OHg=CH-C ONH Nmooou cm CH2CH3CONHi N CHsCHzN NmoccmoltOH3CH2CONH2 (NH OCCH CH NCH CH N (CH CH CONH +4NaOCl+8OH- (CH CH CH NCHCH N (CH CH NH 2 +4NaCl+4CO +4H O Amines of the formula which may beused in the preparation of the starting amides include, inter alia:primary saturated aliphatic amines, such as methylamine, ethylamine,propylamine, butylamine, hexylarnine, octylamine, dodecylamine,etadecylamine; secondary saturated aliphatic amines, such asdimethylamine, diethylamine, dibutylamine, dihexylamine, dioctylamine,dinonylamine, didodecylamine, dioctadecylamine; unsaturated aliphaticamines, such as oleyl amine; aromatic amines, such as aniline, theortho-, meta-, and para-isomers of chloroaniline, ranisidine,phenylene-diamine, aminophenol, nitroaniline, etc. as well as thecorresponding ozand B-naphthylamines and their derivatives. The alkylenepolyamines are also very useful as reactants in this regard. Forexample, in addition to ethylenediamine, there may be employed diethylenetriamine, triethylenetetraarnine, tetraethylenepentamiue as well asthe corresponding polypropylene amines.

Acrylarnide and methacrylamide are particularly suit l able for use inthe process of the invention although other a,,8-unsaturated amides mayalso be used.

The metal hypohalites which may be used to advantage in the new processbelong to the group of alkali metal and alkaline earth metalhypohalites, such as sodium hypochlorite, sodium hypobromite, potassiumhypochlorite and potassium hypobromite as well as calcium hyprochloriteand calcium hypobromite.

The usual alkali metal hydroxides, such as sodium and potassiumhydroxide are especially useful in this reaction to provide therequisite hydroxyl ion.

In general, it is desirable that the reaction involving the conversionof -CONH to NH be carried out in alkaline hydroxylic solvents. From theviewpoint of convenience, it is preferred that this reaction be carriedout in water. Moreover, it is particularly advantageous to keep thereaction temperature during hypohalite addition below 30 C. andpreferably below 15 C., in order to avoid undesired side reactions. Itis of course undesirable for the principal reaction, i.e., theconversion of the amide to the desired amine, be accompanied byundesired side reactions involving e.g. saponification, haloamineformation, or oxidation of the tertiary amine group also present.

The conversion from -CONH to NH may also be effected under anhydrousconditions, e.g. in methanol, using molecular halogen, such as bromine,and methoxide ion as base. Here too undesired side reactions may beavoided by temperature control.

In general, the molar proportions used to advantage in the process ofthe invention are essentially the stoichiometric proportionshereinbefore indicated illustratively in Equations A and B. If less thanthe stoichiometric proportion of hypohalite is used, then the formationof acylurea may take place to an undesirable extent. More than a modestexcess of hypohalite may lead to undesired side reactions. It isadvantageous to use an excess of hydroxide of about one mole per CONHgroup in order to accelerate the reaction, i.e. to achieve a so-calledmass action effect. It has also been found useful in insuring goodyields and temperature control that effective agitation be applied. Thisis particularly important in cases where the tertiary aminoalkyl amidesare reacted in the form of liquid dispersions.

In many specific instances, the reactions described hereinbefore, i.e.the conversion of the amides into thp desired amines and the precedingpreparation of the amides, can be carried out as one continuousoperation without the isolation of the intermediate amides, since thelatter are formed practically quantitatively and can be used in the sameequipment without isolation or purification. This mode of operation is,for example, particularly advantageous in the preparation ofN,N-diethylethylenediamine and N"-methyl diethylenetriamine. The N"designation is conventional for referring to the bridge nitrogen, sothat the last mentioned compound corresponds to the formula 6HzNGHzCHz-NOH;CH;NH2

The amines of the present invention are useful as chelating agents formetals such as zinc, copper, nickel,

cadmium and silver. Thus compounds having the structures (I) and (II):

are described as particularly effective complexing agents inComplexometric Titrations by G. Schwarzenbach (Interscience Publishers,1957, New York).

Schiff bases made from salicylaldehyde and polyamines, such as can beprepared by the process of the present invention, are effective as metaldeactivators in hydrocarbon systems; e.g. the addition of such Schiffbases e.g. to gasoline incorporates into the latter adeactivator-antioxidant eifective against metals such as iron, copper,iron-containing alloys and copper-containing alloys with which thegasoline may come into contact.

The amines of the present invention are also useful as intermediates andas complexing agents. For example, N,N-dimethylandN,N-diethyl-ethylenediamines find utility as intermediates in themanufacture of pharmaceuticals.

The new higher alkylamines provided by the present invention (e.g. thecompounds where R is a dodecyl group or a Z-ethylhexyl group, andespecially N-dodecyl diethylene-triamine) are corrosion inhibitors forferrous metals in acidic aqueous media.

The invention is further set forth with reference to the followingpresently-preferred representative exemplary embodiment. In theexamples, parts are by weight unless otherwise indicated. Therelationship of parts by Weight to parts by volume is the same as thatbetween grams and milliliters. Temperatures are in degrees centigrade.

Example 1 60 parts of sodium hydroxide (1.50 moles) are dissolved in 250parts of water and cooled to 72 parts of N,N-diethyl-aminopropionamide(0.5 mole) are added to the aqueous sodium hydroxide solution and themilky dispersion cooled to 10. 304 parts by volume of aqueous sodiumhypochloride (3.44 N; 0.50 mole NaOCl) are added dropwise over a periodof one hour, the reaction mixture being maintained at 10 to 12 by meansof an ice-water bath. The reaction mixture is allowed to warm up to roomtemperature (about whereupon an exothermic reaction takes place, thetemperature rising to 53, the solution changing in color from almostcolorless to yellowish orange. The reaction mixture is distilled atatmospheric pressure, 210 parts by volume of distillate being collected.75 parts of sodium hydroxide are added to this distillate, whereupon ayellow oil separates (47.5 parts) consisting of over 90 percentN,N-diethyl-ethylenediamine. The N,N- diethylethylenediamine isredistilled over sodium at 139 to 146 at atmospheric pressure yielding44 parts of colorless liquid (or 76 percent of theory).

Analysis (basic nitrogen equivalent weight):

Calculated for C H N 58 Found 59.3

The N,N-diethylaminopropionamide, used in the preceding portion of thisexample, is advantageously prepared as follows.

292 parts of diethylamine (4.0 moles) are added dorpwise at 10 to 15with stirring to an aqueous solution of 284 parts of acrylamide (4.0moles) and 200 parts of water over a period of 30 minutes. The reactionmixture is then warmed at 45 to for two hours and the water removed bydistilling in vacuum. The soobtained N,N-diethylaminopropionamidedistills at 126 to 130 at 0.9 to 1.25 mm. Hg pressure yielding 535part-s of a colorless viscous oil (about 93 precent of theory).

It will be understood that it is not necessary to isolate theN,N-diethylaminopropionamide and that the conversion into theN,N-diethylenediamine may be carried out mutatis mutandis as a part of acontinuous process.

N,N-diethylethylenediamine has heretofore been prepared, e.g. via the,B-aminoethyl hydrogen sulfate; however, the procedure is much moreinvolved than that according to the present invention, and a much loweryield is obtained, as is evident from the following description of theknown process:

147 parts of B-aminoethyl hydrogen sulfate (96%; 0.99 mole) togetherwith 508 parts of water and 223 parts of diethylamine (98%; 3.0 moles)are charged into a stainless steel autoclave and heated with shaking at160 165 and at reaction pressures in the range of 190 to 210 pounds persquare inch. The contents of the autoclave are poured into a largeseparatory funnel, the orange reaction solution being treated with 240parts of 50% aqueous sodium hydroxide and allowed to separate. The upperphase (448 parts) is distilled yielding the following fractions: 7

Temp, 0. Weight Product (parts) (1) 75-78 230 75.8% (C HQZNH. (2) 95-103225 Aqueous solution of N,N-diethylethylenediamine.

Example 2 48 parts of sodium hydroxide are dissolved in 125 parts byvolume of water and cooled to 10. 31.8 parts ofmethylimino-bis-propionamide (0.184 mole) are added to the stirred coldaqueous alkali solution keeping the temperature at 10 or less. .210parts by volume of aqueous sodium hypochlorite (3.89 N; 0.40 mole) areadded dropwise over a period of 30 minutes, stirring at 10 to 12 beingcontinued for 1 hour after addition is complete. The reaction mixture isthen warmed to 30, whereupon an exothermic reaction ensues raising thetemperature to 60. The reaction mixture is heated at to with stirringfor two hours. Analysis of the reaction m'orture indicates that thedesired amine is formed to the extent of 90 percent of theory.

140 parts of sodium hydroxide are dissolved in 390 parts by volume ofthe above reaction mixture, the precipitated inorganic solids beingfiltered off by suction. The filtrate is extracted with about 300 partsof volume of isopropanol, the isopropanol being removed. by distillationat atmospheric pressure through a fractionating column. The residue isdistilled under vacuum yielding 11.5 parts of a colorless oil boiling at93 at 25 mm. Hg pressure. The distilled N"-methyl diethylenetriamine isthus isolated in 54 percent of theory. The so-obtained N"-methyldiethylenetriamine boils at 87 to 89 at 17 to 18 mm. Hg pressure.

Analysis (basic nitrogen equivalent weight):

Calculated for C H N 39.0

The methylimino-bis-propionamide, used in the preceding portion of thisexample, is advantageously prepared as follows:

355 parts of acrylamide (5.0 moles) are dissolved in 500 parts by volumeof water and cooled to 10. 152.6 parts of aqueous methylamine (40.6%;2.0 moles) are added dropwise over a period of one hour, the temperatureof the reaction mixture being kept below a maximum of 41 by cooling inan ice-water bath. The reaction solution is heated at 85 to 90 for 6hours and concentrated to a pale yellow viscous syrup at 10 to 15 mm. Hgpressure. Analysis of the reaction solution at the end of the heatingperiod indicates reaction. The

Analysis (basic nitrogen equivalent weight):

Calculated for CqH15N3O2 173 Found 177 If, in the foregoing, 425 partsof meth-acrylamide are used instead of 355 parts of acrylamide, whileotherwise proceeding as precedingiy described in this example, the finalproduct N"-methyl 2,2'-dimethy1-diethylenetriamine CHZ?HNH2 is obtained,the properties of which are essentially similar to those of the N-methyldiethylenetriamine. In this case, the intermediate amide CHCH(CH3)OONH2CHQN CH2CH(CH3)CONHB is first formed.

Example 3 72 parts of sodium hydroxide (1.8 moles) are dissolved in 405parts by volume of aqueous sodium hypochlorite (0.80 mole) with coolingso that the temperature of the alkaline solution never rises above 10.To the stirred cooled alkaline hypochlorite solution at 3, there israpidly added dropwise, a warm solution of 46 parts ofnitrilo-tris-propionamide (0.30 mole) in 200 I parts by volume of waterso that the temperature during addition is in the range 5 to Thereaction mixture is then warmed to 40 whereupon an exothermic reactionensues changing the color of the solution from pale yellow to orange andraising the temperature to about 70. The reaction mixture is heated for2V2 hours at 90 to 95. The reaction mixture is then cooled to about 40and made acid to Congo red by the cautious addition of concentratedhydrochloric acid. The reaction mixture is concentrated to about 150parts by volume and made alkaline (pH 13 to 13.5) and concentrated todryness. The residue is extracted with successive 100 parts by volumeportions of methanol. The residue from methanol upon distillation yields16.5 parts of tris(2- amino-ethyl)amine boiling at 103 C. at 1.0 mm. Hgpressure, a yield of 56.5% of theory. Upon redistillation the obtainedN,N,N-tris(2-aminoethyl)amine boils at 96-99 C. at 0.80 mm. Hg pressure.

Analysis (basic nitrogen equivalent weight):

Calculated for C T-1 M; 48.7 Found 49.7

The nitrilo-tris-propionamide, used in the preceding portion of thisexample, is advantageously prepared as follows:

5350 parts of a 40 percent aqueous acrylamide solution containing 2130parts of acrylamide (30 moles) is mixed with 2500 parts of concentratedammonium hydroxide (28% NH 41.1 moles) and allowed to stand at roomtemperature for hours. The solution is concentrated in stages toone-third volume at reduced pressures, the precipitated solids beingfiltered 0E, and the filtrate being returned to the still pot forfurther concentration. The combined white crystals are dried in a vacuumoven at 80 and 100 mm. Hg pressure; they melt at 182183'.

(B Theyield is 1662 parts or 72 percent of theory ofnitrilotris-propionamide.

Analysis (basic nitrogen equivalent weight):

Calculated for C H N O 230 Found 228 The tris(2-aminoethyl)amine canalso be prepared via the ,B-aminoethyl phthalimide; however, theprocedure is much more involved than that according to the presentinvention, and much lower yield is obtained as is evident from thefollowing:

150 parts of potassium phthalimide (0.8 mole) and 450 parts of ethylenebromide are heated together at reflux (137) for 12 hours. The reactionproduct is then distilled to recover 306 parts of ethylene bromide. Thereaction product is heated with 300 parts by volume of ethanol andfiltered. The precipitate is washed three times with 50 parts by volumeof ethanol. The ethanol solution is concentrated to dryness and theresidue dissolved in carbon disulfide. The product from carbon disulfidemelts at and weighs parts. The yield of ,B-bromoethylphthalimide is 64%of theory.

50 parts of the so-o'otained B-bromoethylphthalimide (0.02 mole) isheated at 148 to 153 for about 8 hours, anhydrous ammonia being bubbledthrough the melted phthalimide. The product is then taken up in 100parts by volume of ethyl alcohol, the insoluble material being filteredoff. The insoluble precipitate is washed with 100 parts by volume ofethanol once again, yielding 10 parts ofN,N,N-(triphthalimidoethyl)amine melting at 191. This product is heatedat gentle reflux with 200 parts by volume of 6 N hydrochloric acid. Theinsoluble material is filtered ofi and removed. The aqueous solution isevaporated to dryness, washed with methanol yielding 3.5

0 parts of N,N,N-tris(Z-aminoethyl)amine in the form oftrihydrochloride. The yield is 7% of theory for the second step, givingan overall yield of 4.5% of theory.

Example 4 96 parts of sodium hydroxide pellets are dissolved in 600parts by volume of aqueous sodium hypochlorite (4.0 normal; 1.20 moles),the temperature being kept below 10 by external cooling. To the stirredcooled aqueous alkali hypochlorite at 16 are added 68.8 parts ofethylenediaminetetrapropionamide (0.20 mole) dissolved in parts byvolume or" warm water over a period of 20 minutes so that the reactiontemperature is kept at -5 to 0. The reaction mixture is allowed to warmup to 15 over a period of 45 minutes. The reaction mixture is thenwarmed to 40 whereupon an exothermic reaction ensues whichresults in amaximum temperature of about 72 being attained, the reaction solutionbecoming orange in color. To the reaction mixture are added 63 parts ofsodium sulfite (0.5 mole) and the reaction mixture is heated at 95 for 2/2 hours. The reaction mixture is then cooled and cautiously made acidto Congo red with concentrated hydrochloric acid. The acid solution isconcentrated to about 100 parts by volume by distillation at atmosphericpressure, the concentrate then being made alkaline (pH 1313.5) with 50percent aqueous sodium hydroxide. The methanol is removed bydistillation and the residue obtained purified further by treatment with400 parts by volume of 30 percent aqueous sodium hydroxide. Theseparated oil is distilled over potassium hydroxide pellets and boils at195 at 1.2 to 1.5 mm. Hg pressure, yielding 20.2 'parts ofN,N,N,N'-tetrakis(2- aminoethyl)ethylenediamine. The yield is 43.5% oftheory.

The ethylenediaminetetrapropionamide, used in the preceding portion ofthis example, is advantageously prepared as follows:

616 parts of ethylenediamine (85.6%; 88 moles) are added dropwise over aperiod of 45 minutes to a stirred solution of 2982 parts of acrylamide(42 moles) dissolved in 4700 parts by volume of water, the maximumtemperature being kept at 40 by cooling with a water bath. The reactionmixture is then heated at 85 to 90 for four hours and then concentratedby distillation at 15 mm. Hg pressure until white crystals appear in thestill pot. The still liquors are allowed to crystallize spontaneously,the crystal slurry being diluted with an equal volume of methanol andfiltered by suction. 'The yield is 2714 parts (or 91% of theory) ofN,N,N',N tetrakis(2 carbamoylethyl)ethylenediamine(ethylenediarninetetrapropionamide) melting at 171172.

Analysis (nitrogen (Dumas) percent):

Calculated for C H N O 24.42 Found 24.02

Example 5 80 parts of sodium hydroxide (2.0 moles) are dissolved in 310parts by volume of aqueous sodium hypochlorite and cooled to 20. Thealkaline hypochlorite is added dropwise at 5 to over a period of 30minutes to a solution of 68 parts of 2ethylhexylimino-bis-propionamide(93.3%; 0.23 mole) in 200 parts of water. The reaction mixture is thenstirred for 1 hour at room temperature followed by 2 hours at 80.

500 parts of potassium hydroxide pellets are added with cooling,followed by 300 parts of water so that an oily layer separates. Theseparated oil is taken up in isopropanol, filtered by suction and freedof isopropanol by distillation at 15 mm. Hg pressure. The residue isdistilled at 120 to 140 at 0.5 to 1 mm. Hg pressure, the distillate soobtained being then redistilled at 89 to 90 at 0.15 to 0.20 mm. Hgpressure. The product is the desired N"-2-ethylhexyl diethylenetriamine.

Analysis (nitrogen (Dumas) percent):

Calculated fOI' C12H29N3 Found 18.66

The Z-ethylhexylirnino-bispropionamide, used in the preceding portion ofthis example, is advantageously prepared as follows:

130 parts of Z-ethylhexylamine are added dropwise over a period of aboutminutes at 10 to a solution of 166.5 parts of acrylamide (2.3 moles) in500 parts by volume of ethanol. The reaction mixture is then heated withstirring at 8590 for 6 hours and then concentrated by distilling theethanol at 15 mm. Hg pressure. The residual light yellow oil isdissolved in ether, freed of precipitated excess acrylamide by suctionfiltration, the ether being removed by distillation at atmosphericpressure and finally at 1.5 mm. Hg pressure. Analysis of the lightyellow oil indicates that it is 93.3% 2-ethylhexylimino-bispropionamide.

Example 6 80 parts of sodium hydroxide (2.0 moles) are dissolved in 260parts by volume of aqueous sodium hypochlorite (4.03 N) and cooled to 5to 10 by the addition of about 60 parts of ice. The alkalinehypochlorite so obtained is added dropwise over a period of minutes withstirring at a temperature of 10 to 15 to a solution ofn-dodecylimino-bis-propionamide in 200 parts of water. The mixture isthen heated with stirring at 80 for two hours, accompanied byconsiderable foaming. 350 parts of potassium hydroxide are dissolved inthe reaction mixture with warming, whereupon a yellow oil separates. Theseparated oil is dissolved in about 300 parts by volume of isopropanol.The isopropanol is recovered by distillation at 15 mm. Hg pressure andthe residue distilled yielding parts of product boiling at 160 C. at 0.4mm. Hg pressure. The yield is 52 percent of theory. The so-obtainedN-n-dodecylimino-bis-(Z-ethyl- Analysis (nitrogen (Dumas) percent):

Calculated for C H N 15.49 Found 14.64

The n-dodecylimino-bis-propionamide, used in the preceding portion ofthis example, is advantageously prepared as follows:

185 parts of n-dodecylamine, (1.0 mole) dissolved in 70 parts ofmethanol, are added dropwise at 9 to 11 to a solution of 166 parts ofacrylamide (2.3 moles) in 500 parts of methanol with stirring. Thereaction mixture is heated at 65 with stirring for an additional 6hours. An additional 100 parts by volume of methanol are added and thereaction mixture allowed to crystallize spontaneously. The whitecrystals are filtered oif, dried in vacuum at 100 mm. Hg pressure at 60,weighing 274.5 parts representing a yield of 81.5%. The white crystalsmelt at 116 to 117.

96 parts of sodium hydroxide are dissolved in 500 parts by volume ofsodium hypochlorite (4.0 N, 1.0 mole) the temperature being kept below10 by external cooling. To the stirred alkaline hypochlorite at 10 areadded 94 parts of aniline-bispropionamide (0.4 mole) dissolved in 450parts by volume of warm water over a period of 30 minutes, so thattemperature remains in the range of 7 to 3". The greenish blue reactionmixture is stirred at 0 to 10 for 1 hour and then warmed to 30,whereupon an exothermic reaction ensues which results in a maximumtemperature of 70 being reached, the color changing to reddish brown.The reaction solution is heated at 93 to for four hours, during whichthe solution becomes turbid and a dark brown organic upper layerseparates when stirring is stopped. The upper layer is freed of salt bysolution in parts by volume of isopropanol and separation of theprecipitated solids by filtration. The residue from isopropanol yields49.8 parts of N"-phenyldiethylene-triamine boiling at 148- 155 at 1 mm.Hg pressure. The yield is 69.5 percent of theory.

The anilino-bis-propionamide, used in the preceding portion of thisexample, is advantageously prepared as follows:

93 parts of aniline are dissolved in 150 parts by volume of glacialacetic acid, the solution being heated to about 85. 158 parts ofacrylamide are added to the acetic acid solution over a period of 45minutes; the

addition reaction is exothermic and is held to a maximum temperature ofby removing the heat source and controlling the rate of addition. Afterthe addition is complete, the reaction mixture is heated at 80 to 82 forabout 6 hours. The reaction mixture is diluted with 250 parts of waterand made alkaline with aqueous sodium hydroxide. The resulting tanprecipitate is filtered oi'I and dried; it consists of 198 parts ofanilino-bis-propionamide of about 95% purity, representing a yield of80% of theory.

Upon recrystallization from dioxane the .anilino-bispropionamide isobtained as white crystals, melting at 152 after drying.

Analysis (nitrogen (Dumas) percent):

Calculated for C12H17N302 Found 17.64

Having thus disclosed the invention, what is claimed is:N'n'dodecylimmobis'(z'ethylamme) A compound of the formula: ReferencesCited by the Examiner CHzCHzNHz R 5 UNITED STATES PATENTS H 2,681,9356/54 Thompson 260-583 CHzCHzNHg wherein R is alkyl of from 6 to 18carbon atoms. CHARLES B. PARKER, Primqry Examiner.

2. 4-(2-ethy1hexy1)-diethylenetriamine.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No,3,201,472 August 17, 1965 John D Spivack It is hereby certified thaterror appears in the above numbered patent requiring correction and thatthe said Letters Patent should read as corrected below.

lines 37 to 40, for that portion of the form Column 3 line 50, for thatportiol II I d reading Na CO rea SNa CO of the formula reading "(CH CHCH read coluTnn 4, lines .70 to 74, formula (11), lower right-hand 4portion thereof, for "CH CH NH" read CH CH NH --n Signed and sealed this5th day of July 19660 (SEAL) Attest:

ERNEST W. SWIDER Attesting Officer EDWARD J. BRENNP Commissioner ofPatenl

1. A COMPOUND OF THE FORMULA: